


Rotting Like a Lung

by Steve



Category: The Locked Tomb Trilogy | Gideon the Ninth Series - Tamsyn Muir
Genre: Alternate Universe - Role Reversal, Dysfunctional Relationships, F/F, Harrow Nova AU, Power Play, Struggle for Dominance, they're angry! they're horny! they're deeply maladjusted! they're the daughters of the Ninth!!
Language: English
Status: Completed
Published: 2020-12-25
Updated: 2020-12-25
Packaged: 2021-03-10 23:48:32
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,358
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28145631
Author URL: https://archiveofourown.org/users/Steve/pseuds/Steve
Summary: Harrow Nova was no stranger to sacrilege.
Relationships: Gideon Nav/Harrowhark Nonagesimus
Comments: 19
Kudos: 135
Collections: Yuletide 2020





	Rotting Like a Lung

**Author's Note:**

  * For [saltlamppillar](https://archiveofourown.org/users/saltlamppillar/gifts).



> Title is from "Whatever Else Poetry is Freedom" by Irving Layton.

Harrow Nova marched into the private Navamorius library with one hand already on the rapier sheathed at her hip. She would be marking herself the walking dead if she actually drew her naked blade on the Lady of the Ninth House, but at present Harrow felt this a trivial price to pay so long as she could secure the pleasure of spilling her Lady’s intestines across the stone floor.

“How _dare_ you.”

“Good morning to you, too, Harrow.”

The Reverend Daughter Gideon Navamorius lay sprawled on the sofa, and did not even deign to look up from the musty arcane manuscript she was lazily flicking through before addressing her. The gravity of the carefully constructed threat of Harrow’s hand on her rapier, the polished black chain of Samael glittering dangerously across her shoulder, was—as always—utterly wasted on Gideon.

“As if it were not humiliation enough to be denied my rightful claim to the position of cavalier primary,” seethed Harrow, “as if it were not humiliation enough to lose the position to _Ortus_ —you insist on delivering this final, fatal insult—you _dare_ —”

“Rude!” Gideon flipped a page, still not looking at her. “Would it really be so awful to be married to me? _‘Final’_ and _‘fatal’_ , even?”

Harrow lurched forward. She removed her hand from her rapier and grabbed a fistful of Gideon’s collar instead, dragging the Reverend Daughter to her feet. A mess of flimsy fell scattered on the ground.

Her audacity stunned them both. Her fingers trembled against the fabric of Gideon’s shirt, but whether this frailty was caused by a flood of adrenaline and fear, or Gideon’s eyes drifting down to meet hers at last, deep gold and startling as ever—

“I—will _not_ —be married to you,” said Harrow, with surprising steadiness. “I don’t care that you are the lone recognized heir of our House. I don’t care that you’ve already formally petitioned the Reverend Mother and Father. I would rather have skin and sinew flayed from my bone than be married to you. I would rather doggy paddle in the River than be married to you. I would rather wed _Ortus Nigenad_ than be married to _you._ ”

“Okay, now my feelings are _really_ hurt,” drawled Gideon.

She reached up and pried Harrow’s fingers off of her shirt collar, one by one. Harrow let her; Harrow even stepped back several inches, not because she was remotely intimidated by the Reverend Daughter, but because it was difficult to glower in her face and threaten her when she had to crane her neck so much to do it. Gideon’s unholy height advantage was perhaps the most superficial of the many reasons Harrow despised her, but Harrow clung to every God-given reason to despise Gideon with equal ferocity.

“Speaking of Ortus,” Gideon continued, “I should be the one who’s pissed off. Apparently you tried to literally murder my cavalier yesterday?”

“Don’t change the subject,” she snapped.

“Oh, of course. You’d rather discuss our upcoming nuptials.”

“What in the Emperor’s name could I have done to you to deserve this?” Harrow meant the question earnestly, viciously. “I knew you’d threatened, before, to petition, but—”

But she had stupidly, naively assumed it had been just that: a threat, an empty one. A final resort, a last-ditch tool for coercion in Gideon’s arsenal that she would never have to employ, because she already held every card, every possible advantage, while Harrow had nothing but a secondhand rapier, a stolen holy relic, and two hundred dead children screaming in the hollow of her worthless bones.

Clearly she’d underestimated the depths of the Daughter’s depravity, the lengths to which she’d go to watch Harrow squirm just for the hell of it.

“It wasn’t a _threat_ , Harrow,” Gideon said, appalled, as if explaining to a toddler. “And it’s not a punishment. I’m trying to do you a favour.”

She went absolutely cold.

“I don’t want any favours from you. I’ve _never_ wanted _any_ favours from _you._ ”

“The union is barely more than bureaucratic,” Gideon forged on. “Ortus and I are leaving for the Lyctor trials in less than a week. You’ll probably never have to see me again, but this way, you can get your title back, sort of—you’ll even be Reverend Mother one day—you’ll have rights to my supremely impressive genetic material to continue the line—”

“I cannot overstate,” said Harrow, “precisely how little interest I have in your _genetic material_.”

“I can’t believe you’d lie to my face like that. Oh, wait, I totally can.”

She nearly hit her. “Of course this is a fucking joke to you.”

All humour drained from the twitch of the Reverend Daughter’s lips.

“Harrow,” she said quietly, “this is the best chance you’ll get. Otherwise what will you have left, after Ortus and I go? You’ll die here. Miserable and alone. They’ll kill you. I’m afraid they’ll kill you.”

Harrow did hit her, then. She decked Gideon Navamorius across the jaw, then tackled her to the floor so Gideon’s skull knocked back against the cool stone.

“Fucking _hell_ —”

Harrow pushed her knee into Gideon’s gut, pinning her down, wrenching a pained grunt from the Reverend Daughter’s holy lips.

Her own, decidedly unholy lips drew back to bare her teeth.

“You want to do me a _favour_ , Griddle? You want to burn your _pity_ into my flesh like a brand?”

She unsheathed her rapier, and seized Samael Novenary’s chain from where it was slung across her shoulder.

She threw the weapons to the ground, at Gideon’s side.

“Then make me your cavalier. Make me your sword and your chain.” Her fists clenched. Her eyes burned. Gideon was still and warm beneath her. “I have never asked you for anything, Griddle, never. But I am asking you for this.”

 _I have failed in everything I was meant to be,_ she didn’t say aloud. _I am the unfulfilled vow and the bloody teeth of the unkissed skull. Let me fulfill my one remaining purpose, and serve my House with the inadequacy of everything I have left to give._

Gideon reached up to wrap her fingers around Harrow’s wrists.

“It’s bordering personal sacrilege,” she said mildly, “to address your Reverend Daughter so irreverently.”

“Are you going to tell on me?”

“You know I won’t.” She hummed, dangerously contemplative. “I think maybe you should seek absolution in privacy.”

In one quick, fluid motion, Gideon flipped them, reversed their positions so Harrow was the one with her back pressed to the hard floor, the chill of the stone kissing her flesh through the thin fabric of her shirt.

Harrow shuddered.

“It’s not _up_ to me who’s cavalier primary, Harrow. But even if it was...” Gideon shook her head. “You despise me. You resent me. You can’t even bring yourself to be my wife. What makes you think you could be my sword?”

Gideon sat astride Harrow’s chest, unfairly heavy with toned musculature that was wholly unnatural for a necromancer, especially a necromancer as prodigious as the adopted Reverend Daughter. But Gideon had always been bigger and stronger than Harrow, as likely to throw a clumsy punch as she was to summon a construct, though she could do the latter gorgeously and without a hint of blood sweat.

To compensate, Harrow trained from the age of five for agility, precision, and wholesale nastiness.

She leaned up. She bit Gideon’s thigh, plunging her incisors into Gideon’s meat without hesitation or restraint. The hot, wet tang of blood gushed across her tongue. Gideon howled.

The ensuing battle was swift and savage.

Harrow did not take up her blade. Gideon did not take up her bones. Their weapons stayed within reach but untouched, and the two girls struggled bodily on the floor like they were nothing but feral, lonely children again.

In the end, as she always, _always_ did, Gideon emerged on top. Harrow was faster, smarter, better-trained, but none of that ever mattered here. The same lesson had been hammered into her teeth, over and over. It never stuck.

Gideon straddled one of her legs, her hands pinning both of Harrow’s wrists to the floor, this time careful to keep every part of her body out of range of her mouth. They were both panting and bloody and sore.

“As prenup talks go,” the Daughter remarked, “this could have gone better.”

Harrow thrashed beneath her, briefly overtaken by the intense, helpless desire to ram her skull into Gideon’s nose.

Gideon just laughed, adjusting slightly to reinforce the pinning grip she had on her. A streak of sweat and blood crawled down the long brown column of her throat.

Her knee shifted between Harrow’s legs, slid upward. Harrow gasped. They both froze.

“Harrowhark,” the Reverend Daughter, the usurper, the personified reminder of the unrelenting failure of her existence said very slowly, “are you _getting off_ on this?”

Denial, furious and reflexive, rose to her lips. Heat flushed through her face and curled between her legs, throbbing at the crucial point where Gideon’s knee pressed into her.

Denial flickered and died.

It was supplanted by grim, horrible focus, the intensity of which she had not felt since she was five years old and climbing the Anastasian monument, her every step an act of desecration, of violation, of worship.

Too busy with her own astonished glee, Gideon had foolishly loosened her grip on Harrow’s wrists. Harrow seized this opportunity to break the hold entirely.

She reached up and cupped a hand between the Daughter’s legs.

Gideon jerked. Most vitally, she arched into Harrow’s touch, rather than away. Her breath escaped in a juddering stutter.

“It seems,” Harrow said in her best attempt at a neutral tone, “I’m not the only one _getting off._ ”

“You absolute freak,” Gideon breathed. She shifted, tried to grind down into Harrow’s hand, but Harrow withdrew as abruptly as she’d reached out.

Gideon groaned. Shameless and indecent, everything the Reverend Daughter of Drearburh was never meant to be.

“You say I can’t be your cavalier,” said Harrow, “because I despise you, because I resent you. And I do, with every miserable cell of my being. But I can also do my duty while despising and resenting you.”

She reached out again, gripped Gideon’s thigh hard enough to bruise, her thumb grazing the gouges left earlier by her teeth.

“Say the word, _Reverend Daughter_ , and I am your creature _._ Allow me to prove I can keep my vows.”

Gideon peered down at her, gold eyes hot and gleaming. Assessing.

Then her knee slid even higher, grinding into Harrow. Like an experiment, a question. Harrow’s own body betrayed her, and answered with a bone-deep shudder, a flaring clench of heat.

“Okay,” said Gideon, arriving at a decision.

She slid off of Harrow, who was mortified to discover how her body mourned the loss of warmth and weight.

Harrow craved.

Gideon murmured: “Roll onto your stomach.”

She flushed. “What—”

“You’re asking what I want? You’re asking for instruction from your Lady and necromancer?” Beneath the mask of her face paint, there was a strange edge to Gideon’s face, soft and hungry at once. “What I want is to _fuck you into the floor._ But I have a feeling that’s not what you had in mind.”

No, it was not what Harrow had in mind. Harrow thought Gideon would want to get off, quick and easy and predictable. Harrow had anticipated—had privately gotten rather attached to—the slippery prospect of unraveling Gideon, of using her fingers and tongue to prove she could act capably as Gideon’s sword and chain.

The Daughter smirked, a tiny, familiar, infuriating crook of her mouth. “That’s what I thought.”

But before she could get up, turn away—

Emperor forgive her: Harrow snapped a hand around her wrist.

“Make me,” she said.

Gideon’s eyes went wide.

She heard the words for what they were: not only a challenge, but desperate, blasphemous invitation.

They beheld each other, necromancer and cavalier, transplanted Reverend Daughter and unfulfilled blood debt.

Then Gideon bent down and cupped Harrow’s jaw in a touch so gentle that Harrow wanted to scream, wanted to sink her teeth into the smooth flesh of Gideon’s fingers for the insult.

But the hand was dropped before Harrow could do much more than tremble. Gideon took her by the shoulders and flipped her over, belly-down, and Harrow complied like a broken ragdoll; a coward; an eager, horny idiot of mythic proportions.

She lay prostrate before the Daughter she despised and resented, something she had never done without someone’s boot bearing down on her neck. This time nothing held her there except the whisper of Gideon’s hand trailing her spine, the slick heat pooling between her legs, and some blinding, dizzying swell of emotion that she could not name but robbed her of what little reason she possessed.

Harrow held herself very, very still as Gideon positioned herself behind and above her. She gripped Harrow by the nape of her neck and dragged her up so Harrow was on her knees. Her steadfast weight and heat pressed into Harrow from behind, wrapped around her, her arms holding Harrow up as much as they were holding her in place. It was familiar and alien; echo and reversal both of how Gideon had emerged on top in their fights before.

A pair of hands, too-large and teeth-shatteringly familiar, wandered down Harrow’s collar, the flat plane of her chest, the taut muscle of her abdomen. They never dared to even slip under her shirt. Harrow shook; she longed to flinch away, longed even more to debase herself and curl herself into Gideon’s touch, let herself be swallowed in her small, starved, wretched entirety.

But here Gideon paused entirely, as though this was as far as she had planned. It struck her that Gideon had very little idea what she was doing, just as Harrow had very little idea what _she_ was doing.

But Harrow Nova was no stranger to sacrilege.

She reached for Gideon’s hand where it curled uselessly across Harrow’s abdomen, and dragged it down to her waistband.

This seemed to galvanize the Reverend Daughter.

“Eager much, Nova?” she breathed into her ear. “I suppose I shouldn’t be surprised.”

Harrow considered bucking her off right then, but her breath hitched as Gideon’s hand—large and unblemished and soft, always the opposite of Harrow’s own—dove beneath the waistband of her trousers.

Another shudder rolled down Harrow’s spine. Gideon’s warm body sank over Harrow’s while Gideon’s warm fingers sank into her, and with nowhere else to escape the heat that enfolded them, Harrow pressed her forehead to the cold stone of the floor.

It wasn’t supplication. But it did resemble prayer.

The hand that wasn’t currently fucking into Harrow buried itself in Harrow’s hair. For a moment she was afraid Gideon would drag her head up, maybe tilt her face toward hers to meet her gaze, but instead her fingers merely rested atop Harrow’s scalp, holding her in place.

She found herself deeply relieved.

Gideon of course had to ruin it by speaking.

“You’re soaking,” she muttered. It came out less like a taunt and more like a statement of awe. Her breath tickled Harrow’s ear, and Harrow desperately wished it _had_ been a taunt, a plain insult instead of one disguised.

“Griddle—”

Whatever retort she hoped to form was lost. Two fingers plunged knuckle-deep, stretching her open, and Harrow would have welcomed the ache—if not for the thumb that began stroking over her clit, lazy and rough.

It was far, far too much; it could never hope to be enough.

Harrow gasped into the floor, then slapped her own palms over her mouth to smother the soft whimper threatening to leak out. She would not, could not give Gideon the satisfaction. Not when Gideon Navamorius was fucking her the way Gideon Navamorius did everything: with laziness, arrogance, and the singular purpose of wrecking Harrow’s life.

Harrow bit down on her palm until she tasted blood.

Behind her, a muttered, exasperated curse.

Skeletal fingers ensnared her wrists. Harrow’s hands were wrenched away from her mouth and slammed to the hard ground above her head, caged and pinned by a slick, knobbly bone construct.

“Nice try,” Gideon breathed, teeth scraping the shell of her ear, “but I want to hear you, Harrow.”

“Fuck you,” she spat.

“You always were stubborn to the point of absurdity,” Gideon said, almost _fond_.

As she spoke, she flicked Harrow’s clit with something like playfulness. Harrow bucked violently. If her face wasn’t already pressed into the ground, she could have cracked open her skull.

“For once in your fucking life,” said Gideon, “just let go.”

Fingers twisted into her hair, pushed her face harder into the jagged stone floor. Her eyes stung with hot tears. And she almost did, for once in her fucking life, just _let go._

Then Gideon made a fatal mistake.

The pressure on Harrow’s head vanished. Instead, soft fingers brushed a sweat-soaked lock of hair from the nape of Harrow’s neck, a whisper of warmth that bloomed over Harrow’s skin like consecration, like blight.

Gideon pressed her lips to Harrowhark’s shoulder in a tender kiss.

Harrow snapped. Harrow _broke._

She reared up. Osseous matter dusted the floor as she punched through the flimsy bone hands that had been pinning hers in place. Gideon fell away from her, her fingers wrenching out of Harrow so abruptly that Harrow felt sick and dizzy and empty.

She expected Gideon to cry out in surprise, in exasperation, but there was nothing.

Harrow couldn’t speak, either. She was trembling. Her shoulder burned where the kiss had landed. Her neck, her chest, her jaw—her flesh crawled in every place that had borne the indignity of Gideon’s gentleness.

The Daughter opened her mouth as if to say something. It was thanks to twelve bitter years of honing her reflexes with Aiglamene that Harrow moved now as fast she did.

She fisted her hands in Gideon’s collar, as she had done before, and she hauled them both upright. She slammed Gideon down against the surface of the desk. Gideon’s teeth clacked together as her skull hit the wood. She gazed up at Harrow with those unfathomable yellow eyes, and she did not move to fight back.

She said: “ _Harrowhark._ ”

Harrowhark closed her hand around the Daughter’s throat.

Her thumb dug into the wet, throbbing point of Gideon’s pulse. In response, heat clenched between Harrow’s legs, stinging where Gideon’s fingers had been thrusting into her only seconds prior.

Gideon did not flinch or thrash. She was pliant beneath her, eyes fluttering half-shut. An obscene sound leaked from her lips, something between a gurgle and a whine.

Most vitally, she leaned up into Harrow’s hand.

Harrow released her as if scalded.

But Gideon remained lying back against the desk, and Harrow remained looming over her, their legs pressed together, meat to meat.

“You are vile,” said Harrow.

“Your paint is smeared,” Gideon retorted.

She suspected she was lying. Gideon’s own sacramental skull of the Unhallowed Scream had stayed pristine. But the way Gideon beheld her, the burn of her eyes may as well have been peeling the paint off her skin. Harrow felt bare, felt seen, stripped naked like when she had been a child forced to kneel before the Reverend Father and the altar and Gideon, Gideon, _Gideon._

Gideon, whose fingers were still sticky and slick with Harrow, whose palm had settled on the knot of Harrow’s hip bone without either of them registering.

This time, Harrow did not snap. They both stayed very still. They remained.

It was impossible to know who dropped their gaze first. But Harrow was the one who took a step back, and allowed the Daughter to rise from where she had been pinned to the desk.

“I’ll go talk to my parents,” Gideon Navamorius said curtly, smoothing down her collar. “You should report to Aiglamene. Let her know the Ninth House’s new cavalier primary will need to be suitably equipped.”

Gideon swept out of the room without glancing back.

The Ninth House’s new cavalier primary picked up her sword and her chain, after the trembling finally passed.


End file.
